Lead-free potassium bismuth titanate thin film with complex Aurivillius layer structure

Abstract

A ferroelectric thin film of Aurivillius phase K 0.5 Bi 4.5 Ti 4 O 15 (KBT) with a complex bismuth layer-structure was fabricated using the pulsed laser deposition method. The thin film grown on Pt/Ti/SiO 2 / Si substrate shows a strong c-axis orientation, as revealed by x-ray diffraction results, and platelike growth of grains. A Pt/ KBT/Pt capacitor shows a maximum polarization of about 20 µC/cm 2 . In addition, the capacitor also shows good fatigue resistance, with a decrease of 14.5% in the remanent polarization after 10 7 switching cycles. This Aurivillius phase with four layers of TiO 6 octahedra in its unit cell has a band gap of 3.6 eV, which is greater than that of Bi 4 Ti 3 O 12 . KeywordsLead, free, potassium, bismuth, titanate, thin, film, complex, Aurivillius, layer, structure Disciplines Engineering | Physical Sciences and Mathematics Publication DetailsCheng, Z, Wang, P, Zhao, H, & Kimura, H (2010), Lead-free potassium bismuth titanate thin film with complex Aurivillius layer structure, Journal of Applied Physics, 107 (8) A ferroelectric thin film of Aurivillius phase K 0.5 Bi 4.5 Ti 4 O 15 ͑KBT͒ with a complex bismuth layer-structure was fabricated using the pulsed laser deposition method. The thin film grown on Pt/ Ti/ SiO 2 / Si substrate shows a strong c-axis orientation, as revealed by x-ray diffraction results, and platelike growth of grains. A Pt/KBT/Pt capacitor shows a maximum polarization of about 20 C / cm 2 . In addition, the capacitor also shows good fatigue resistance, with a decrease of 14.5% in the remanent polarization after 10 7 switching cycles. This Aurivillius phase with four layers of TiO 6 octahedra in its unit cell has a band gap of 3.6 eV, which is greater than that of Bi 4 Ti 3 O 12 .

Structure and Dielectric Properties of BaTiO3–BiYO3 Perovskite Solid Solutions

“…Relaxor ferroelectrics have been extensively studied for the Multilayer Ceramic Capacitor(MLCC) applications, due to their high dielectric constant and low temperature coefficient of permittivity, including lead‐based perovskites PMN–PT, PNN–PZT, PLZT, etc. However, more research has been devoted to lead‐free relaxor materials because of the environmental restriction in last two decades, where the modified BaTiO 3 ceramics have been investigated for MLCC applications, such as Ba(Ti, Zr)O 3 , Ba(Ti, Sn)O 3 , Ba 1− x Bi 2 x /3 TiO 3 , and (Na 1− x K x ) 1/2 Bi 1/2 TiO 3 . The Bi 3+ ion is a promising alternative to Pb 2+ ion due to their similar lone‐pair 6 s 2 electronic configuration.…”

Large magnetoelectric coupling in magnetically short-range ordered Bi5Ti3FeO15 film

“…Recently, a novel class of materials with the general formula of (Bi 2 O 2 ) 2+ (A m-1 B m O 3m+1 ) 2− (m: number of pseudo-perovskite layers) and an Aurivillius layer structure has come to our attention1516. This class of compound is naturally ferroelectric at room temperature, with very high ferroelectric transition temperatures, such as 1021 K171819.…”

Influences of ScTa co-substitution on the properties of Ultra-high temperature Bi3TiNbO9-based piezoelectric ceramics

“…However, the piezoactivity of pure BTNO ceramics is quite low (d 33 <7 pC/N) [10] for high temperature applications. The A-site substitution or/and B-site substitution have been shown to be effective in modifying the structure and polarization process [11][12][13][14][15][16][17][18][19][20][21][22][23]. Only a few works have addressed the properties of cation-modified BTNO-based ceramics.…”